Neighborhood Plum Jam

A week or so ago, I was bemoaning my lack of plums. I used to rent a house with the most gloriously productive Santa Rosa plum tree you could imagine. During my first two summers of canning, I picked and jammed so many plums that I thought I would never want to see a plum again. Not so. After moving out of that house and passing a couple of plumless years, I found myself longing for that old tree.

So far, my search for a new source of free, backyard Santa Rosa plums has been– well — fruitless. But what about the legions of little red and yellow plums dropping off trees in every other yard and sliming sidewalks from one end of town to the other? Do you have plums like that where you are? Have you tasted them? Some of them are really good.

I went looking and found rogue plum trees in vacant lots and around the shaggy edges of parks. I found them hanging over fences, where they dropped their unwanted fruit on my shoes. I started picking. And I had help. Here’s a text exchange with a good friend, who shall remain anonymous lest she be nabbed by the neighborhood plum police . . .

I don’t want to know exactly how she did it, but a day or so after our conversation, she presented me with a bag of red jewels. I mixed those plums with fruit from two other trees to make neighborhood plum jam.

This recipe is different from the ones I usually post. The ingredients are simple — plums, sugar, lemon juice, a bit of optional booze — and the process is easy. That said, the precise measurements depend on how many plums you glean and on your own taste, so what I’m going to do is try to provide some basic instructions for building your own jam. (For inspiring some of the underlying methods, I’m grateful for the beautiful Blue Chair Jam Cookbook, by Rachel Saunders.)

1. Begin by pitting and then weighing your plums. These little guys weren’t very willing to separate from their pits, so I used a sharp knife to cut away as much flesh as I could. Weigh your plums after you pit them, but consider this twist: Because the plums are small and the ratio of skin to flesh is high, I put about a third of my plums through a food mill before weighing. (I wanted my jam to be tart, but not as tart as all of that skin would likely make it.) I composted the skins caught in the mill, mixed the resulting pulp together with the rest of the chopped plums, and weighed that. I found that I had 5 1/2 pounds of plum stuff in my bowl.

2. Decide how much sugar you want to use. I suggest an amount that is 50%-70% of the total weight of your plums. My plums were a bit tart, so I decided to go for about 65% sugar, and I love how it turned out. First, I converted the weight of my plums to ounces: 5 1/2 pounds of plums equals 88 ounces. I multiplied 88 by .65 to determine that 65% sugar would be roughly 57 ounces, or about 3 1/2 pounds. Are you with me? (I’m actually not very good at these kinds of calculations and often have to ask Stewart for help.) You can fudge the numbers a little bit one way or the other. It will be okay.

Step 2: Let the Plums and Sugar Get Acquainted

Combine the sugar and chopped plums in a big glass or ceramic bowl, cover the bowl tightly, and let it rest in the refrigerator for 12-24 hours.

Step 3. Make Jam

1. Prepare your jars (they’ll need to be hot but not necessarily sterilized, because the processing time is 10 minutes) and put 5 metal teaspoons on a plate in the freezer to test your jam for doneness later.

2. Stir 2 ounces of lemon juice into the plum mixture. Taste it. You should be able to detect the juice, but just a hint of it. If you don’t taste any lemon, stir in a little more juice until you reach the level you like. (Add the juice just a little at a time. Too much will create a burn on the tongue and, like salt, you can’t take it back.)

3. Transfer the mixture to an appropriately sized jam pan and bring it to a boil, stirring frequently. Cook the jam at a steady boil, monitoring it carefully and stirring enough to prevent sticking or scorching. As the jam cooks, skim the foam with a large, shallow, stainless-steel spoon. Turn down the heat as moisture evaporates and expect to be stirring the jam slowly and almost constantly for the last 10 minutes or so of cooking time. My jam, cooked in an 11-quart pan, was done in about 35 minutes, but your cooking time will depend on many factors, including the amount of fruit, the size of your pan, and the heat of your stove. Test the jam for doneness when it has thickened, the foam has settled down, and the bubbles are small and shiny.

To test your jam for doneness: Remove the mixture from the heat. Use one of your frozen spoons to scoop up a little bit of jam — not a whole spoonful. Return the spoon to the freezer and wait 3 minutes. Retrieve the spoon and hold it vertically. If the mixture looks almost like it wants to run, but can’t, and it has substantially thickened, it’s done. Alternately, give the mixture a little push with your finger. If you see creases or wrinkles, it’s ready. If the jam runs, cook it for 2-3 minutes more (stirring all the while) then test again.

4. Remove the jam from the heat and skim any remaining foam. If you’re inclined to stir in a splash of something — a couple tablespoons of bourbon or brandy — now would be the time.

5. Pour the jam into hot jars, leaving 1/4-inch head space. Wipe the rims clean, apply the two-piece lids, and process in a hot water bath for 10 minutes, adding time for your elevation if necessary.

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36 Comments

Mmmmmm…plum jam. One of our neighbors at our old house had a FANTASTIC plum tree that hung over our fence. Since that made them legally ours, we picked them every day for the whole month they were ripe. We actually had to put a limit on the number of plums the kids could eat in a day to avoid ill effects (if you know what I mean). That tree that wasn’t even in our yard is about the only thing I miss from that house!

Wendy, I thought that was the law of hanging fruit, too, but I checked Nolo’s Neighbor Law and it says the fruit of the tree belongs to the tree owner, even if they hang over another person’s property. Sounds like your neighbors had more than they wanted, in any case. Oh, and I do know what you mean. :-)

Hey There!!! Love this post :) And the texting is hysterical too….I adore plum jam. I pair Plum, Apricot and Crystallized Ginger with Cointreau and the results are quite yummy if I say so myself!! (a project for your next plum heist) I always macerate overnight in sugar and lemon as you do here.

Last year I foraged a few wormy plums from my brother’s tree and gave him a couple jars of jam….he liked it so this year he took better care of his tree and I’ve done 3 batches of jam (one whole batch for my brother!) and a batch of chutney. Then my DIL got some too! Yummmmmm.

I get so sad when I see fruit going to waste. I’m glad your friend was able to snag those plums before they passed their prime. We used to have two mystery plum trees and we ate the fruit and made jam and chutney with those funny little plums. There were so many. I gave big bowls away. They were pretty good, but the Santa Rosa plums on my neighbor’s scrawny Charlie Brown-like tree, those were the best. Enjoy your neighborhood jam!

I really like how you tested your jam- I have never heard of testing with metal spoons in the freezer. Now I just need to remember to put the spoons in the freezer before I start. I really wish that I would get around to planting fruit trees on our property, especially since they take some time to mature. Congratulations on your heist.

Hi Jenn! It’s the same as the frozen plate test; it’s just a little easier to manage with the spoons. Sometimes I forget to put the spoons in the freezer, too, but you can toss them in there halfway through and it will still work.

My friend told me a very simple way to separate the flesh from pit and skin. I used it and it worked like a charm! Freeze the whole plums. When you’re ready to make jam, let the plums thaw to room temp. Then squish the thawed plums with your hands and it all separates! This worked great for me.
P.S. Every time I ask someone if I can pick fruit off their tree, they seem relieved! Avocados, loquats, oranges, lemons–most of these trees produce way too much for one family.

Technically, fruit on a neighbor’s tree, even if it hangs over into your yard, is the neighbor’s by law in many places. I’m sorry your friend decided not to ask but steal plums. Doesn’t make for good neighbors. We have lots of young trees of many types of fruit. I can only use so much. If I catch someone helping him/herself, I will call the police. But a simple knock on the door will result in a smile and a “sure, let me get you some!” Had your friend asked, she may have been the recipient of more tasty plums in the years to come… And maybe would have made new friends in the process.

Letty, that’s the law here, too. I agree with you that it’s always best to ask. I also trusted my friend to assess this particular situation. She’s a good girl, and the text exchange was intended to be lighthearted. We often joke like that, but I appreciate this opportunity to clarify that I don’t wish to encourage anyone to steal.

Made this jam last night – I couldn’t resist after reading your wonderful blog. This will become one of my favorites. The only addition I made was of a few spoonfuls of a sweet Shiraz named appropriately enough Jam Jar that we discovered at our anniversary dinner- awesome all around. Thank you so much!

Deb, that’s wonderful! Thanks for coming back to tell about it. I love the idea of a wine named Jam Jar, and plums with wine sounds like a killer combination, too. That’s one of my favorite things about simple jams like this one — just a little shift brings out the jam maker’s personality!

I’ve been going with a ratio of 50% sugar to fruit these days. Depends on the fruit, though, as you point out! My apricots were so, so tart, I could have bumped them up. But also was worried that I might do too much sugar.

I have two such little-plum trees in my backyard! Since the plums are approximately cherry-sized, I always just use a cherry pitter to separate the pits from the flesh–much quicker than a sharp knife, in my hands!

Lisa, I tried my cherry pitter (both of them, actually) but all of my plums were too big to fit into it. I didn’t mind using the sharp knife. We had company hanging around in the kitchen, so I just sliced and talked and sliced and talked. (Watching what I was doing, of course!)

Reminds me of my life in MV when we walked up and down the hilly streets with baggies and picked Santa Rosa plums, those little yellow ones and the red heart ones up from the side of the road. We did the neighborhood a favor as they get pretty messy and slippery. Congrats on the ribbons too!
I have been out of touch for a month…so good to catch up.

Thanks for your stories: the fair the pigeons and the jammin’ I enjoy them very much. My trick for separating pits from pesky plum-mutts is to roast them in a large roasting pan until they have released their juices and as soon as they are cool enough I pull out the pits (no waste). Then I use a immersion blender to puree them and proceed on to cooking pot.

The plums I get are coastal (as in Bolinas) and take a lot longer to ripen and loaded with pectin so they are jam in no time at all. Thanks again for a lovely blog and looking forward to your e-book.
Congratulations on all your success!

I found your article while hunting for a forum to offer the fruits of my brimming Santa Rosa Plum tree. Are you still looking for plums? Let me know! I have lots of them, they are ripe, and I would love to share them with other plum enthusiasts. Let me know!

Look at that, you are in the middle of the bush and still helping me out. Plums showed up at our Farmers Market today. I knew you would have a boozy plum recipe. Have you seen Jack Daniels Whiskey with Tennessee honey yet? It is my new best friend in the kitchen. Sometimes I even add it to what I am making! :0

I found your blog while desperately seeking another way to use up the plethora of yellow plums that my tree produced this year. I found a recipe that called for using orange peel and orange liqueur in the jam. I have also been using a blackberry liqueur which has worked very well. We have a bumper crop of blackberries and I also made a plum jam where I substituted 1 cup of fresh blackberries for 1 cup of plums that turned out great.

That all sounds wonderful. I often add orange-related ingredients — juice, zest, liqueurs, once even some previously preserved orange slices — to plums; it’s a great combination. I love little-yellow-plum jam, too!